package com.wxy.learn.jackson;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializerProvider;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;

import java.io.IOException;

/**
 * JacksonConfig
 *
 * @author wxy
 * @since 2022-01-23
 */
@Configuration
public class JacksonConfig {
    @Bean
    @Primary
    @ConditionalOnMissingBean(ObjectMapper.class)
    public ObjectMapper jacksonObjectMapper(Jackson2ObjectMapperBuilder builder) {
        ObjectMapper objectMapper = builder.createXmlMapper(false).build();
        // 屏蔽掉值为null的参数
        objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);

        /// 修改值为null的参数值(需要处理打开方法并修改逻辑)
        /*objectMapper.getSerializerProvider()
                .setNullValueSerializer(new JsonSerializer<>() {
            @Override
            public void serialize(Object o, JsonGenerator jsonGenerator,
                                  SerializerProvider serializerProvider) throws IOException {
                jsonGenerator.writeString("");
            }
        });*/
        return objectMapper;
    }
}